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Full text of "The Morphology And Evolution Of The Apes And Man"

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the well-developed crest for the attachment of the anterior bellies of the digastric muscles; these muscles must have been fused as in the modern Macaque Monkeys. The symphysis ends immediately in front of the digastric ridge, and is not separated from it by a flat area of bone as in the Apes. Smith Woodward points out that the adult Ape differs from Dryopithecus and from the new-born Ape in this antero-posterior elongation of the bony chin. No mylo-hyoid line exists. There is a single mental foramen a considerable distance below the first premolar tooth. The large symphysis and the deep body show that the masseter muscles must have been very powerful. Smith Woodward concludes that the mandible is of a generalized type, which " resembles the large modern Anthropoids no more closely than it agrees with the earliest known true Man. By slight changes in two different directions it may have passed into the one as readily as into the other." The lower molar teeth increase in the order 1, 2, 3. They have the usual five cusps, of which three lie on the external and two on the internal side, the hypoconulid being lateral instead of mesial in position. The outer cusps are more worn than the inner cusps, and the protoconid is surrounded by. an external girdle or cin-gulum. The enamel is devoid of wrinkling. Other species show differences in the cusps, cingulum and crenation of the enamel; and the teeth of some species are relatively larger than those of others.
The femur of Dnjopitliecus was discovered in the sands of Eppelsheim. Dubois pointed out that it resembles the femur of the Gibbons, and gave the specimen the name Pliohylobates eppelsheimensis. Schlosser showed that it really belongs to Dryopithecus.